powerpc/kprobes: Remove resume_execution() in kprobes

[safe/jmp/linux-2.6] / arch / powerpc / kernel / kprobes.c

diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 4ba2af1..bc47352 100644 (file)
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -31,12 +31,13 @@
 #include <linux/preempt.h>
 #include <linux/module.h>
 #include <linux/kdebug.h>
+#include <linux/slab.h>
 #include <asm/cacheflush.h>
 #include <asm/sstep.h>
 #include <asm/uaccess.h>
 #include <asm/system.h>
 
-#ifdef CONFIG_BOOKE
+#ifdef CONFIG_PPC_ADV_DEBUG_REGS
 #define MSR_SINGLESTEP (MSR_DE)
 #else
 #define MSR_SINGLESTEP (MSR_SE)
@@ -96,9 +97,10 @@ void __kprobes arch_disarm_kprobe(struct kprobe *p)
 
 void __kprobes arch_remove_kprobe(struct kprobe *p)
 {
-       mutex_lock(&kprobe_mutex);
-       free_insn_slot(p->ainsn.insn, 0);
-       mutex_unlock(&kprobe_mutex);
+       if (p->ainsn.insn) {
+               free_insn_slot(p->ainsn.insn, 0);
+               p->ainsn.insn = NULL;
+       }
 }
 
 static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs)
@@ -109,9 +111,12 @@ static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs)
         * like Decrementer or External Interrupt */
        regs->msr &= ~MSR_EE;
        regs->msr |= MSR_SINGLESTEP;
-#ifdef CONFIG_BOOKE
+#ifdef CONFIG_PPC_ADV_DEBUG_REGS
        regs->msr &= ~MSR_CE;
        mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM);
+#ifdef CONFIG_PPC_47x
+       isync();
+#endif
 #endif
 
        /*
@@ -144,7 +149,6 @@ static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs,
        kcb->kprobe_saved_msr = regs->msr;
 }
 
-/* Called with kretprobe_lock held */
 void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
                                      struct pt_regs *regs)
 {
@@ -312,13 +316,12 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p,
        unsigned long trampoline_address =(unsigned long)&kretprobe_trampoline;
 
        INIT_HLIST_HEAD(&empty_rp);
-       spin_lock_irqsave(&kretprobe_lock, flags);
-       head = kretprobe_inst_table_head(current);
+       kretprobe_hash_lock(current, &head, &flags);
 
        /*
         * It is possible to have multiple instances associated with a given
         * task either because an multiple functions in the call path
-        * have a return probe installed on them, and/or more then one return
+        * have a return probe installed on them, and/or more than one return
         * return probe was registered for a target function.
         *
         * We can handle this because:
@@ -352,7 +355,7 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p,
        regs->nip = orig_ret_address;
 
        reset_current_kprobe();
-       spin_unlock_irqrestore(&kretprobe_lock, flags);
+       kretprobe_hash_unlock(current, &flags);
        preempt_enable_no_resched();
 
        hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
@@ -375,17 +378,6 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p,
  * single-stepped a copy of the instruction.  The address of this
  * copy is p->ainsn.insn.
  */
-static void __kprobes resume_execution(struct kprobe *p, struct pt_regs *regs)
-{
-       int ret;
-       unsigned int insn = *p->ainsn.insn;
-
-       regs->nip = (unsigned long)p->addr;
-       ret = emulate_step(regs, insn);
-       if (ret == 0)
-               regs->nip = (unsigned long)p->addr + 4;
-}
-
 static int __kprobes post_kprobe_handler(struct pt_regs *regs)
 {
        struct kprobe *cur = kprobe_running();
@@ -403,7 +395,8 @@ static int __kprobes post_kprobe_handler(struct pt_regs *regs)
                cur->post_handler(cur, regs, 0);
        }
 
-       resume_execution(cur, regs);
+       /* Adjust nip to after the single-stepped instruction */
+       regs->nip = (unsigned long)cur->addr + 4;
        regs->msr |= kcb->kprobe_saved_msr;
 
        /*Restore back the original saved kprobes variables and continue. */